MXPA97010000A - New polies style - Google Patents

Abstract

The present invention relates to tow which is suitable for processing in a combed wool or woolen fabric system consisting essentially of continuous polyester filaments which are a mixture of high denier and low denier filaments and having a serrated oval cross section or another cross section that is generally oval in shape, but with grooves or channels running along the length of the filaments. Such polyester tows provide improved processing on the combed wool systems to provide threads of three or more polyester films and mix with wool, and fashion items, such as fabrics and garments.

Description

NEW POLYESTER STOP This invention relates to a new polyester tow, and more particularly relates to a polyester tow that is suitable for conversion to a mech, or U? CÍI dt; 6 ± bLtMit dt; wool peiüctüd u Lej d? ictua and the subsequent processing of such systems, and with the rexaciopactos processes with this and the products o.e xa same. All synthetic fibers, including fibers of poiiéster 0, can be classified into two groups, namely (i) continuous filaments and * 2) fibers that are discontinuous, to rip -mac iilr -i "c-rin iaanal ae f ror , Pr r '' = 5 &? ~ \ ac rr rr \ r r ^ mr ^ staple fibers this invention provides improvements relating to the "orocesamiento latter group, 5 although such staple poiiéster fibers must be first formed. by extrusion in continuous podster filaments, which are processed in the form of a tow of continuous polyester filaments. This invention provides a new tow of continuous polyester filaments which provides the advantage of being able to be better processed subsequently of the combed wool system. To a large extent, the objective of the synthetic fiber producers has been to duplicate the advantageous properties REF: 26011 of natural fibers, the most common of which have been cotton and wool fibers. Most of the polyester staple fibers have been round cross section and have been mixed with cotton. A typical three or more textile yarn is cotton of number 25, and of cross section containing approximately 140 fibers of 1.5 dpf (denier per filament) and 1.5 inches in length. It has been custom to equal the pfd and the length. The denier is the weight in grams of 9000 meters of fiber and in this way a measure in effect of the thickness of the fiber. When one refers to the denier, it often refers to the nominal or average denier since there is an inevitable variation along end to end, ie along the length of a filament and between the different filaments, respectively. In general, it has been the objective of the fiber producers to achieve the highest possible uniformity in all the steps of processing throughout and end to end to produce a polyester fiber of round cross section and of a single denier and of a uniform denier. as much as is practical. 1.5 dpf and 1.5 inches in length corresponds to 1.7 dtex and to case 4 cm. Polyester strands / worsted are different from the threads of polyester / cotton, they are typically worsted number 23, and cross section containing about 60 fibers for single yarn and about 42 fibers yarn double game, with fibers that have been 4 dpf and 3.5 inches in length (4.4 dtex and case 9 cm). The number of the yarn can vary from combed wool 55 to combed wool 10, while denier and length can variously up to about 4.5 (5 dtex and 11.5 cm) and down to about 3 (3.3 dtex and 7.5 cm) ). Until relatively recently, the advantages of using lower pfd synthetic fibers than the corresponding natural fibers (such as wool) have been found to be practical and / or recognized. Recent inventions for providing low dpf polyester fiber to be mixed with wool in the combed wool system, however, have not been successful, and require improvements. When the denier of the fiber has been reduced, the fiber becomes difficult to process (load, tuck, comb, etc.) in the spinning mill. Indeed, under a certain fiber denier, the polyester fibers we have tried have been practically impossible to process and / or have given poor quality fabrics. Thus, to process and mix in a commercially acceptable manner with wool in practice, we have found that the denier of the fiber of such polyester fibers must be at least about 3 dpf (3.3 dtex). It is believed that up to now there are no commercially available dpf (nominal) tow of less than 3. This has been the state for a long time in the market. In this way, try to manipulate the desire to reduce the pfd to resemble being very contradictory or incompatible with the processability in the satisfactory spinning mill. The processing in the combed wool system is totally different for the major practice currently carried out in the cotton system, which generally uses cotton fiber that is sold in bales or bales and that can be mixed with polyester fiber which is mainly fiber cut, which is also sold in bales or compacted bales. In contrast, for the processing in our system, the operators of the combed wool system have to buy a tow of polyester fiber (instead of a compacted bundle of cut fiber) so that they can convert the tow (which is continuous) in a continuous wick or toral (a continuous end of discontinuous fibers, hereinafter referred to briefly as "cut fiber") by a compression cut and stretch break. This wick or twine is then processed (as a continuous end) through several stages, i.e., tucked in, stained, reextracted, combed, tucked or stretched, and generally, finally mixing with wool. It is very important, when processed in the combed wool system, to maintain the continuity of the wick or twine. Also, however, it is important to be able to treat the fiber cut into the wick appropriately while maintaining a satisfactorily reasonable processing speed for the continuous wick or twist. As indicated, recent attempts to use desirable polyester tow, for example, with low dpf, have not produced the desired results. For example, unsatisfactorily low machine productivity rates have been required after staining; it is believed that this may be due to the fact that such polyester fiber has been previously packed very strongly. According to one aspect of the invention, a tow is provided which is suitable for processing in a combed wool or woolen fabric system and consisting essentially of continuous polyester filaments of an average denier per filament of up to about 4.5, ie of a titre up to about 5 dtex per filament, where the polyester is a branched chain polymer, the filaments are a mixture of higher denier filaments per filament and lower denier filament per filament, the lower denier is in the denier range of 0.5 to 2.5 (which is approximately the same title as the range of 0.5 to 3 dtex) per filament and the highest denier is in the denier range of 2 to 5 (which is roughly the same title) that the range of 2 to 6 dtex) per filament and is at least 1.5 times that of the lower denier, such filaments have a cross section that is generally oval shaped with grooves, and the Anuras run along the length of the filaments. It is believed that the intentionally mixed denier polyester tow has not previously been sold for processing in the woolen or combed wool fabric system. Such a polyester tow is usually sold in large tow boxes. It is believed that boxes of such intentionally mixed denier polyester tow have not previously been sold for processing in such systems. It is in the fashion and processing products that the advantages of the invention are mainly demonstrated, as will be illustrated hereinafter. Such advantages are particularly significant for lower pfd products, but such improvements are also available for normal pfd. Therefore, such fashionable products are also provided, according to the invention, especially wicks or twists of continuous combed wool system polyester fiber (cut), and yarns, fabrics and garments of such wicks or twines. , including blends of polyester fiber and wool fiber and / or, if desired, other fibers, and processes for their preparation and / or use. According to a preferred aspect of the invention, there is provided a process for preparing a tow of crimped polyester filaments, stretched for conversion into combed worsted polyester yarns, where the tow is a mixture of denier polyester filaments intentionally different, such process comprises the steps of forming bundles of denier filaments differing as desired from polyester polymer prepared with a chain branching agent, and generally oval with slots running along the length of the filaments, spinning through capillaries at different flow rates preferably on the same spinning machine, using radially directed air cooling from a profiled cooling system, collecting such bundles or bundles of different denier filaments, and combining them into a tow, and subjecting the filaments to Stretching and curling operations in the form of such tow. Figures 1 and 3 are amplified photographs of cross sections of filament as will be explained hereinafter in more detail; Figure 1 shows a mixture of higher dpf filament and lower dpf according to the invention; Figures 2 and 3 show different examples of generally oval filament cross sections with grooves running along the length of the filaments, such as those that can be used (in mixtures of higher and lower dpf) in tow according to to the invention, including fashion products.

Figure 4 is a block diagram showing the typical process steps by which a tow of the invention can be prepared. Figures 5, 6 and 7 are stress and strain curves for single and higher denier filaments as will be explained here in more detail later. Figures 8 and 9 plot the coefficient of friction versus the velocity for filaments of oval cross section cogged denier and for filament of round cross section of a single dpf (ie not mixed), Figure 8 is for friction fiber to fiber, while Figure 9 is for fiber to metal friction. As indicated, this invention relates to polyester filament tow which is suitable for processing in combed wool or woolen fabric systems. Presently, such tow as commercially available are believed to have been bundles or bundles of continuous filaments, stretched, crimped, of round filament cross section with a denier generally of about 900,000 each filament is about one denier 3. The denier is a metric measurement, it has to know the weight in grams of 9000 meters of fiber and in this way a measure in effect of the thickness of the fiber. When one refers to the denier, it often refers to the nominal or average denier, since there are inevitably variations along and end to end, that is, along a length of filament and between different filaments, respectively. In general, it has been the goal of the fiber producers to achieve the highest possible uniformity in all the steps of end-to-end processing to produce a polyester fiber with a round cross section and a single denier and a denier tan. uniform as is practical. This is the current commercial practice in the production of tow for processing in the combed wool system. In contrast, the present invention provides mixed dpf polyester tow, using filaments of different (non-round) cross section, and using branched chain polymer. Gpndstaff, in US Patents 5,188,892 and 5,308,564 disclose polyester filaments mixtures of different dpf (and, if desired, different cross sections) for a different purpose. Grindstaff was concerned with providing cut polyester fiber for processing into the cotton fabric system, which is very different and has different requirements. Gpndstaff does not teach a tow of filaments of my cross-sectional type, nor of my type of polymer (branched chain), nor of my cooling system, nor for my purpose or end use, although it teaches mixed deniers (of filaments of its types) ). The description of Grindstaff, however, is expressly incorporated herein by reference, since its description explains many of the steps for preparing a tow of polyester filaments, despite the differences, of the current filaments of use and the different intended purposes. . The present invention, however, is primarily directed to providing a polyester tow (stretched polyester filaments, crimped into a bundle or bundle, and including the resulting twine) for processing in the combed wool system, requirements for which they are known in the art and differ to some degree from those for the woolen fabric system. The terms "fiber" and "filament" will often be used here in an inclusive manner, without pretending that the use of one term should exclude the other. The cross sections of the polyester filaments used according to the present invention should be round but generally oval in shape with grooves running along the length of the filaments. Typically, such a cross section is an oval, serrated cross section, as described by Gorrafa in U.S. Patent No. 3, 914,488, the description of which is hereby expressly incorporated by reference. The tows of such filaments are described and illustrated in the Examples herein below, and an amplified photograph (1000X) of both types of filament is shown in the Figure of the Drawings accompanying the present. Figure 2 shows an oval cross-section, toothed to an even larger amplification (3000X). The term "oval" is generic and includes elongated shapes that are not round, but which have an "aspect ratio" (ratio of length to width of the cross section) that is greater than 1, preferably greater than about 1 / 0.7 (corresponding to a length of the major axis A: length of the minor axis B as described by Gorrafa 1.4); and preferably less than about 1 / 0.35 (which corresponds to the Gorrafa preference of up to about 2.4), at least as regards the dentate oval shape. The provision of slots (indentations or channels) is also important according to that described by Gorrafa and in the related art and in my co-pending patent application DP-6365 No. 08 / 497,499, filed simultaneously with this on June 30, 1995, the description of which is here expressly incorporated by reference, and which has somewhat different preferences for aspect ratios, as described herein. Figure 3 shows such a cross section of a preferred hexagonal channel polyester filament at a magnification of 1000X.

The curling and stretching and many other products and process conditions and characteristics have already been described in the art, for example those referred to. The polyester polymer used to produce the filaments should be branched chain, as indicated in the Examples. This technology has been widely described in various techniques, including Mead and Reese in U.S. Patent 3,335,211, MacLean et al. in U.S. Patents 4,092,299 and 4,113,704, Reese in U.S. Patent 4,833,032, EP 294,912, and the technique described herein, by way of example. Tetrasilicate (TES) is preferred as the chain brancher according to the present invention. The amount of chain brancher will depend on the desired result, although 0.3 to 0.7 mol% polymer is generally preferred. The polyester polymer should desirably be essentially homopolymer 2G-T (another having chain chain content), ie poly (ethylene terephthalate), and should preferably be of relatively low viscosity, and it has been found that LRV polymers of about 8 to about 12 give very good results as indicated hereinafter in the examples. As described by Mead and Reese, one advantage of using TES is that it hydrolyzes later to provide a desirable low stacking product. However, the use of radially directed cooling air from a profiled cooling system according to that described by Anderson et al. in U.S. Patent 5,219,582, especially when spinning such a low viscosity polymer. Relative viscosity (LRV) is defined in Broaddus, U.S. Patent 4,712,988. As indicated in the Examples hereinafter, the proportions of higher and lower denier filaments may vary, for example, from 5 or 10 to 90 or 95 percent of each type. Generally speaking, however, approximately equal amounts will give very good results, for example, 40-60% of each type of pfd when two pfd are mixed in the tow, and about one third of each when three types are mixed, by example. Those and other variations will often depend on what is desired in fashion products, such as fabrics and clothing. Aesthetic considerations are very important in garments and other textile applications. Worsted wool apparel applications include, for example, men's and women's suits, separate garments, baggy garments, coats, military and career uniforms, durable garments and knit garments. knitted. As indicated hereinafter and in the background above, the tow of the invention (including its resulting wicks or lathes) can be processed with advantages in the combed wool system. The typical process preparation steps are illustrated schematically by means of a block diagram in Figure 4 of the Drawings, and are also described hereinafter in the Examples; they generally follow normal procedures, except as described herein, especially since the present invention relates to filaments having more than one filament denier, both (or all) of which are prepared and then mixed instead of one Single denier filament tow (nominal). As described in some of the Examples, similar wadding rates are preferably used by spinning position, so that the bundle or bundle of extruded filaments encounters similar heat loads during cooling of the freshly extruded bundle or bundle, this with frequency may be advantageous during subsequent processing, such as the simultaneous stretching of the tow. The invention is best illustrated in the following Examples, which, for convenience, refer to processing in the combed wool system, which is generally more important, although the tows of the invention could also be processed in a woolen fabric system. All parts and percentages are by weight unless otherwise indicated. Most test procedures are well known and / or described in the art. To avoid doubts, the following explanations of the procedures that were used in the following paragraphs are given. The measurements were made using conventional US textile units, including the denier, which is a metric unit. To comply with prescriptive practices in any place, they are given in dtex and CPcm equivalent of the DPF and CPI measurements in parentheses after the current measurements. For measurements of tension, or traction, however, the current measurements in gpd have been converted to g / dtex and the latter have been given. The ripple frequency was measured as the number of crimps per inch (CPI) after crimping the tow. The ripple is exhibited by numerous peaks and valleys in the fiber. The filaments were removed from the random bundle or tow and placed (one at a time) in a relaxed state in the fasteners of a fiber length measuring device. The fasteners were manually operated and initially moved sufficiently close to prevent stretching of the fiber while being placed in the fastener. One end of a fiber was placed in the holder on the left, and another end in the holder on the right of the measuring device. The bra on the left was rotated to move any braid or twist in the fiber. The support bracket on the right moved slowly and gently to the right (extending the fiber) until the slack of the fiber was removed but without removing any curl. Using an illuminated amplifier, the number of peaks on the upper and lower side of the fiber was counted. The bra holder on the right then moved slowly and gently to the right until all the curls disappeared. Care was taken not to stretch the fiber. This length of the fiber was recorded. The curling frequency of each filament was calculated as: Total Number of Peaks 2 x Strand Length (not curled) The average of 10 measurements of the 10 fibers was recorded for the CPI (curls per inch). The CTU (curl length ratio) was measured on the tow which is a measure of the length of the extended tow, to remove the curl, by the length not extended (ie, crimped), expressed as a percentage, as described in Anderson et al, U.S. Patent No. 5,219,582.

The stress and strain curves were obtained as follows as an average of 10 individual filaments of each type taken from the bundle of tow. Samples from each of the highest and lowest denier filaments were separated from the bundle of tow using an amplifier glass (LUXO Illuminated Amplifier). The denier (per filament, dpf) of each sample filament was measured on a VIBPOSCOPE (Model 201C HP Audio Oscillator). The sample filaments were then assembled at the same time in an INSTRON (Model 1122 or 1123) and the behavior of the stresses and deformations was measured. The breaks for each type of filament were recorded, and the averages of 10 samples were recorded for each filament type. The frictions of the fiber were obtained using the following procedure. A block of fibrous material with a weight of 0.75 grams was made by placing fibers in an adhesive tape one inch wide by eight inches long (25 x 200 mm). For fiber-to-fiber friction measurements, 1.5 grams of fibers were attached to a two-inch (50 mm) diameter tube that was placed on a rotating tube of a mandrel. One end of the block of test fibrous material was attached to a strain gauge and hung on the fiber-covered mandrel. A weight of 30 grams was attached to the opposite end and the stresses were measured as the mandrel rotated at various speeds over a range of 0.0016-100 cm / sec. When the fiber to metal friction was measured, a smooth metal tube was used instead of the tube covered with 1.5 grams of fiber, but the procedure was similar. The coefficients of friction of the stresses that were measured were calculated.

EXAMPLE I Filaments of poly (ethylene terephthalate) of blended dpf, being approximately 40% by weight of pfd of 6.0 (dtex of 6.7), being 60% by weight of pfd of 9.4 (dtex of 10.4) and spun by melting at 282 ° C from polymer containing 0.40 mol percent tetraethyl orthosilicate (as described in Mead, et al, US Patent 3,335,211) and having a relative viscosity of 10.1 (determined from the 80 mg solution of polymer in 10 ml of hexafluoroisopropanol solvent at 25 ° C). The polymer was extruded at a rate of 90 pounds / hr (41 kg / hr) per position of 44 total positions. 17 positions, with 9 positions one on each side of the machine and 8 positions on the other, produced the denier filaments low (6.0). 27 positions, with 13 positions on one side and 14 positions on the other, produced heavy denier positions (9.4). The shape of the orifice of each of the capillaries of the nozzle for spinning was of three diamonds joined to give filaments of oval cross-section, toothed, according to that described by Gorrafa in the US Patent 3,914,488. The smaller filaments were spun from a spinneret containing 711 capillaries while the longer filaments were spun from a spinneret containing 450 capillaries. All those filaments were spun at an extraction speed of 1600 ypm and cooled using radially directed air from a profiled cooling system, as described in Anderson, et al. U.S. Patent 5,219,582. The spun tow was collected in a tubular bovine and consisted of a mixture of lower and higher denier filaments, this being according to the invention. The total denier of the tow was approximately 187.096, and the total number of filaments was 24.237. The properties of the spun filament are indicated in Table IA. The average strain and strain curves of a single filament (taken from the tow) are shown in Figure 5 for lower and higher dpf filaments.

TABLE IT Twelve tubular yarn supply bovines were combined to give the amount of 290,844 filaments and a total denier of approximately 2.3 million (dtex of 2.6 million). This tow was extruded at a stretch ratio of 3.0X in a water spray extruder at 95 ° C. It was surprising that it was possible to stretch an intimate mixture of yarn filaments of different denier simultaneously (whose natural stretch ratio had not been adjusted to the same stretch ratio in the same tow), ie to give stretched filaments that were satisfactory and without dark staining defects. In other words, it was surprising that it was possible to spin those undrawn filaments of this polyethylene terephthalate (modified with tetraethyl orthosilicate) which had been significantly different denier yarns on the same spinning machine without adjusting the natural stretch ratio and then subsequently stretched to provide filaments with excellent properties (which are different due to their different dpf) and to provide fabrics and garments eventually with superior tactile properties. The tow was then passed through a filler machine box curling machine and subsequently relaxed to 130 ° C to give a final tow with a total denier of approximately 861,000 (dtex of 957,000), effectively denier of about 3 average. dpf (dtex of 3.3), but contained filaments of both higher and lower denier in the same 40/60 ratios. The stretching properties are illustrated in Table IB.

TABLE IB a conventional finish was applied to provide a fiber finish level of 0.15% by weight. The tow was collected in a conventional tow box and sent to a spinning mill for further processing, mixing with wool, and yarn conversion.

The successful spinning processing of the tow (including cutting to form a continuous wick, staining, and tucking, combing, etc.) is critical to commercial viability. Poor retraction results in loss of process efficiency and / or unacceptable product quality. It was surprising that the processing of the tow and the wick resulting from the present example (with mixed denier fibers, oval cross-section, toothed) was significantly superior to the processing of a similar tow, except that it contained fibers of round cross section (and dpf not mixed), and it is believed that the latter was possibly difficult to process due to the effect of unacceptably high levels of fiber to fiber friction, and fiber to metal during the different tucking operations. The friction characteristics of the two types are shown and compared in Figures 8 and 9.

EXAMPLE II The filaments of oval, serrated, similar cross section were spun in approximately equal amounts (by weight) of lower denier (dpf of 3.1) (dtex of 3.4) and of higher denier (dpf of 7.2, dtex of 8.0), but essentially in a manner similar to the procedure described in Example I at a rate of 70 pounds / hr. (32 Kg / hr) by position of a 48-position spinning machine. Twenty-four positions, with 12 positions on each side of the machine, produced lower denier filaments. Likewise, twenty-four positions, with twelve positions on each side of the machine, produced the highest denier filament. The smaller filaments were spun from spinning nozzles containing 1.054 min capillaries that the larger filaments would be spun from nozzles for yarns containing 450 capillaries. The total denier of the spun tow was approximately 156,178 (approximately dtex of 173,500). The spin properties are indicated in Table 2A. The stress and average strain curves (as for Example I) are shown in Figure 6.

TABLE 2A Fourteen tubular yarn supply coils were combined to provide a total denier tow of approximately 2.2 million, which was stretched, crimped, and relaxed essentially as described in Example I to give a final tow with a size of approximately 812,000 (dtex) of 902,000) denier (902,000). The stretching properties are listed in Table 2B: TABLE 2B A conventional finish was applied, as in Example I. The effective / nominal denier was a dpf of 2.0 (dtex of 2.2), approximately 50% of the filaments (by weight) was of dpf of 1.2 and 50% was of dpf of 3.0 (see Table 2B). The tow was collected in a conventional tow box and sent to a spinning mill for further processing, mixing with cloth, and yarn conversion. It is surprising that the tow of this Example was processed well through the various spinning mill processing steps involving compression cutting to a specified length, dyeing and tucking because a tow consisting of round fiber geometry thereof dpf (2) (not mixed) is not processed in an acceptable manner because it causes problems of productivity, efficiency and quality. In Example VII hereinafter, a lower dpf filament tow was made and processed successfully.

EXAMPLE III In Example I, a tow of filaments of mixed dpf filaments of oval, serrated cross section having 60% of larger dpf filaments and 40% lower dpf was spun. This Example III was carried out using essentially the same procedure, except that the proportions were 50/50 (again by weight), roughly adjusting the number of ends (spin positions), which were spun (extruded) in lower and higher dpf filaments and, where necessary, the number of capillaries per end (spin position). Thus, for the 50/50 mixture, an equal number of spinning nozzles (22 of each) of 450 capillaries per end and 1054 capillaries per end were used at flow rates of 90 pounds (41 Kg) / hr./extreme . Those tow and their wicks showed good characteristics of later processing. The data is tabulated in Table 3, TABLE 3 EXAMPLE IV In Table 4, the data for spun fibers is summarized essentially as described for Table 3, but for filaments prepared by a procedure essentially the same as that described in Example II, and where the relative proportions and the denier varied. Thus, for the 60/40 mix, 29 spinning nozzles and 711 capillaries / end, and 19 spraying nozzles with 1054 capillaries / end were used to cause 70 pounds (32 Kg) per hour per end. Those tow and their wicks showed good characteristics of later processing.

TABLE 4 EXAMPLE V Fibers of poly (ethylene terephthalate) dpf 3.2 (dtex 3.6) were spun down essentially as described in Example 2, but extruded at a rate of about 7.3 pounds (33 kg) / hr. from a single position of a spinning nozzle containing 1054 capillaries and wound on a coil to give a denier of filament bundle of 3445 (dtex of about 3830). The dpf filaments of 7.8 (dtex of 8.7) were similarly spun by fusion and wound on a coil to give a bundle denier or bundle of 3492 (3880 dtex) being extruded at a rate of about 75 pounds (34 Kg) / hr. of a nozzle that contained 450 capillaries in this unique position. The properties of the yarn are indicated in Table 5A: TABLE 5A The coils of those lower dpf filament and the 29 coils of those higher dpf filaments were combined to form a tow having a nominal dpf filament mix ratio lower / higher than 10/90 for simultaneous drawing . The tow stretched to a stretch ratio of 2.6X is a water spray stretcher at 95 ° C. The tow was then passed through a filler machine box filler and subsequently relaxed to 145 ° C to give a final tow size with a denier of approximately 47,000 (52,000 dtex) of an intimate mixture containing filaments of lower and higher denier, with a nominal (average) dpf of approximately 3.0 (dtex of 3.3), whose filament properties are listed in Table 5B: TABLE 5B A conventional finish was applied as in Example I. The tow was collected in a conventional tow box and sent to a spinning mill for further processing, mixing with wool for the yarn conversion and then into fabrics. How a tow (and the resulting wick or twine) is processed in a spinning mill is critical to commercial viability. To estimate the performance of the product in the spinning mill, wick cohesion tests were carried out, a measure of the fiber to fiber bending, before and after the staining. The wick cohesion tests consist of loading to make a wick of 12 inches (approximately 30 cm) in length, holding the wick vertically and adding weights to the bottom until the load support limit is reached (ie, that the fibers in the wick are pulled separately and the weights fall). For dyed articles, the wicks were tightly compacted in nylon bags and press-stained at 250 ° F (121 ° C) for 30 minutes with disperse blue G / F dye. The samples were dried in a forced air oven at 270 ° F (132 ° C) for 30 minutes and the cohesion of the wick was measured in mg / denier (mg / dtex given in parentheses). Such tests reflect the magnitude of the change in flexural properties between articles before and after staining. For comparison, wick cohesion tests were performed on round fiber rovings of dpf of 3.0 (dtex of 3.3) (of the same polymer and of CPI (8.2) and ripple index (3.2 CPcm)) currently sold commercially. The results of the wick cohesion tests are given in Table 5C.

TABLE 5C A comparison of the cohesion values of the wick obtained show that the wick of the tow of the invention (mixed dpf of oval cross-section, toothed) had much lower values of cohesion of wick, only 30% of that of the wick of type of single fiber dpf (not mixed), conventional (also of dpf of 3), before staining and only 36% of the staining after the conventional type. That may explain in retrospect why the tow of the invention (and its resulting wick) are processed much better.

EXAMPLE VI In Table 6, the data is summarized for mixed dpf filament tow prepared essentially as described for Example V, but where the relative concentration of denier higher and lower in their respective deniers varied. As explained above, the denier was varied by changing the rate of polymer flow through the capillaries, while the relative concentration in the mixture was varied by changing the number of ends (coils) of a given denier in the mixture. before stretching The following abbreviations were used in the headings in the Table: "TP / end" indicates flow rate (per end) and was measured in lbs; "Fils" indicates the number of capillaries, that is, the number of filaments per end, "Bs" indicates the number of ends between (coils) combined before stretching; "%" indicates the proportion (by weight) of each dpf in the stretched tow; and SI equivalents are given, for example, after lbs (kg), after DPF (dtex), after CPI (Cpc), and calculated between (g / dtex) instead of gpd, which were actually measured , as was done previously.

TABLE 6 EXAMPLE VII A tow of mixed dpf of poly (ethylene terephthalate) filaments in a mixture of about 80% by weight of dpf of 3.1 (dtex of 3.4) and 20% by weight of dpf of 7.2 (dtex of 8) was prepared by spinning by fusion (from polymer containing 0.58 mol percent tetraethyl orthosilicate having a relative viscosity of 8.9) essentially as described in Example II, except that 38 positions, with 19 positions on each side of the machine and 19 positions on the other side, produced the lowest denier filaments and 10 positions, with 5 positions on one side and 5 on the other side, produced the highest denier filaments. Spun tow collected in a tubular bovine had a total denier of approximately 157,000 (174,000 dtex). The properties of the yarn are indicated in Table 7A. The stress and strain curves on average (as for Examples 1 and 2) are shown in Figure 7.

TABLE 7A Fifteen tubular yarn supply bobbins were combined for a total tow denier of approximately 2.2 million (2.4 million dtex), which was stretched, curled and relaxed essentially as described in Example I to give a final tow size with a denier of approximately 900,000 (dtex of 1,000,000) and of an effective nominal denier of approximately 1,5 (dtex of 1,7). The resulting properties are listed in Table 7B: TABLE 7B A conventional finish was applied as in Example I. The tow was collected in a conventional tow box and sent to a spinning mill for further processing, including compression breaking, followed by mixing with wool, conversion to yarn, and cloth manufacture.

EXAMPLE VIII Processed dpf tow yarns were processed essentially as described in Example III, Article 1, including drawing at different drawing or extraction (DR) ratios so that the final product could be scrutinized at the level of product quality defects , as indicated hereinafter in Table 8. Product defects can be classified into three categories: 1) Equivalent Factory Defects (EFD), 2) Defect of Dark Stain (DDD), 3) Fragmentations (SPL). The first two defects (EFD and DDD) are fibers and blocks of fibers that stain darker than normal fibers. The DDD have a diameter less than 4X the diameter of fiber (stretched) normal. The EFD have a diameter 4X the diameter of normal fiber or greater.

Both defects must be longer than 0.25 inches (approximately 6 mm). The samples were processed through a loader of the upper roller type. The wick was stained light blue and visually examined under an illuminated amplifier glass. The fibers that were stained darker than the rest of the sample were removed, classified as EFD or DDD and counted. Each type of defect was reported as the number of defects per 0.1 pound (0.05 Kg) of wick. Fragmentations are fibers or blocks of oversized fibers. To be classified as fragmentations, this defect must be longer than approximately 0.25 inches (approximately 6 mm) and the total diameter must be greater than 0.0025 inches (64 μ). Fragmentations concentrate on the disposal of flat strips when a cut sample is processed through a flat loader. The waste of flat strips was examined visually against a black background. The fragmentations were removed, classified by size, counted, and expressed as the weight based on the sample.

TABLE 8 In other words, the quality of the product was not adversely impacted by the variation of the draw ratio over such stretching range, and those different stretching ratios did not result in observable fiber defects. In addition, the flow rate of the stretching machine was not reduced by the broken or rolled filaments in the roller.

EXAMPLE IX The tows made essentially as described in Example II were treated with a durable silicone elastomer finish before being mixed with wool. A 20% aqueous emulsion of amino methyl polysiloxane copolymer was made at a concentration of 0.25% in a water bath at room temperature. The tow was processed at a rate of 8 lbs. (4 kg) / hr. through the bath and dried in an oven at 300 ° F (149 ° C) for 5 minutes to cure the silicone. The resulting silicone level in the fiber was 0.3%. The application of this silicone improved the softness and elasticity of the resulting fibers, because it reduced the friction fiber to fiber and thread to thread, to give an aesthetic somewhat better similar to previous experience with the application of silicone lubricants to fill the fiber to be used in stuffed items.

EXAMPLE X Filaments were spun and wound with a dpf of 3.2 (dtex of 3.6) as described in Example V to give a coil of such filaments with a total bundle denier of 3445 (dtex of about 3830).

Filaments with a dpf of 7.3 (dtex of 8.1) were prepared from the same polymer and essentially similar except that they were extruded at a flow rate of 70.8 lbs. (32.1 kg) / hr. of a spinning nozzle containing 450 capillaries in this single position and wound on a coil with a total bundle denier of 3284 (approximately 3650 dtex). Strands of 11.4 dpf (dtex of 12.7) were prepared in a similar manner, except that the polymer was extruded at a rate of 59.8 lbs. (27.1 kg) / hr. of 243 capillaries in a single position and rolled into a coil to give a total bundle denier of 2771 (dtex of about 3080). The properties of the yarn are indicated in Table 10A: TABLE 10A Eleven small dpf coils, 12 medium dpf coils, and 14 large dpf coils were combined to create a tow having about 33% by weight of each large, medium, and small dpf for a total tow size with a denier 115,000 (dtex of 128,000). This tow was stretched, curled, and relaxed as described in Example V to give a tow size with a denier of approximately 50,000 (55,000 dtex) of an intimate blend containing light, medium, and heavy denier filaments. Their properties are listed in Table 10B.

TABLE 10B A conventional finish was applied as in Example I. The effective / nominal denier was a dpf of 3.1 (dtex of 3.4), with approximately 33% by weight the length, 34% the medium, and 33% the small. Accordingly, this Example shows that the invention is not limited to tow containing only two different dpf, but that more than two may be included in such tow, and their corresponding wicks and subsequent products.

EXAMPLE XI Mixed poly (ethylene terephthalate) dpf filaments mixed simultaneously (from a polymer containing 0.5 mole percent tetraethyl silicate and having a relative viscosity of 8.9) were extruded from a single position at a total speed of 92. pounds / hr. (42 Kg / hr) of a spinning nozzle containing 1000 capillaries and wound on a coil at 1800 ypm (1650 mpm). The spinneret had 484 capillaries with a flow area of 0.000222 square inches (0.143 mm square) for lightweight dff fibers and 516 flow area capillaries of 0.000272 square inches (0.175 mm square) for heavy dff fibers. The small capillaries were located in the five inner rings while the larger capillaries were located in the four outer rings of the spinning nozzle. The light dpf obtained was 3.5 while the heavy dpf was 4.6 with an effective average dpf of 4.25 (dtex of 4.6) and one denier under total filament 4093 (dtex of 4548). The properties of the yarn are indicated in Table HA: TABLE HA Thirty-four dpf filament coils mixed from the yarn were combined to form a tow with a nominal dpf filament mixing ratio lower / higher than 40% / 60% for simultaneous stretching. The tow was stretched at a stretch ratio of 2.6X in a water spray stretcher at 95 ° C. The tow was then passed through a filler machine box curling machine and subsequently relaxed to 145 ° C to give a final tow size with a denier of approximately 56,000 (62,000 dtex) of an intimate mixture containing filaments of denier lower and higher, with a nominal (average) dpf of about 1.85 (dtex of 2.1), whose filament properties are listed in Table 11B.

TABLE 11B A conventional finish was applied as in Example I. The tow was collected in a conventional tow box and sent to a spinner for further processing, mixed with wool for the yarn conversion and then into fabrics. The Examples have shown how the filament tows of the invention can be prepared and processed, including their wick processing, and subsequent processing into yarns, fabrics and garments. The aesthetics of the later final articles is very important, and all textile processing is done from that point of view.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects that it refers.

Having described the invention as above, property is claimed as contained in the following:

Claims (2)

1. A tow that is suitable for processing in a combed wool or woolen fabric system and consisting of continuous polyester filament with an average titer per filament up to dtex of 5, wherein the polyester is a branched chain polymer, the filaments they are a mixture of filaments of higher title by filament and filaments of lower title by filament, the lowest title is of a dtex of 0.5 to 3 per filament and the highest title is of a dtex of 2 to 6 per filament and it is at least 1.5 times the highest title, and wherein the cross sections of the filaments are generally oval-shaped with ves, and the ves run along the length of the filaments.

2. A wick or twist that is suitable for processing in a combed wool or woolen fabric system and consisting of a continuous wick or twist of discontinuous polyester fibers or wool fibers and discontinuous polyester fibers, wherein the polyester is a branched chain polymer, and where the polyester fibers are a mixture of higher title fibers per fiber and lower title fibers per fiber, the lowest titre is a dtex of 0.5 to 3 per fiber and the title the highest is a dtex of 2 to 6 per fiber and is at least 1.5 times the title to the lower title, and wherein the cross sections of the polyester fibers are generally oval-shaped with ves, and the ves run lengthwise of the length of the polyester fibers.